Environment Variables

Variable	Default	Description
`OPEN_SPANNER_HTTP_ADDR`	`:18081`	API listen address.
`OPEN_SPANNER_GRPC_ADDR`	`:18090`	gRPC listen address for backend usage ingestion.
`OPEN_SPANNER_DB_DRIVER`	`sqlite`	Storage driver: `sqlite` or `postgres`.
`OPEN_SPANNER_SQLITE_PATH`	`open-spanner.db`	SQLite database path.
`OPEN_SPANNER_POSTGRES_DSN`		Postgres connection string when `OPEN_SPANNER_DB_DRIVER=postgres`.
`OPEN_SPANNER_DB_MAX_OPEN_CONNS`	`0`	Maximum open SQL connections; `0` keeps Go's default.
`OPEN_SPANNER_DB_MAX_IDLE_CONNS`	`0`	Maximum idle SQL connections; `0` keeps Go's default.
`OPEN_SPANNER_DB_CONN_MAX_LIFETIME`	`0`	Maximum SQL connection lifetime; `0` disables recycling.
`OPEN_SPANNER_DB_CONN_MAX_IDLE_TIME`	`0`	Maximum SQL connection idle time; `0` disables idle-time recycling.
`OPEN_SPANNER_EXPORT_STORAGE_PATH`	`open-spanner-exports`	Directory used by the API and export worker for generated export files.
`OPEN_SPANNER_EXPORT_WORKER_INTERVAL`	`5s`	How often the export worker checks for queued jobs.
`OPEN_SPANNER_EXPORT_WORKER_LOCK_TTL`	`5m`	Lease duration for a claimed export job.
`OPEN_SPANNER_EXPORT_WORKER_TIMEOUT`	`10m`	Maximum processing time for one export job.
`OPEN_SPANNER_EXPORT_WORKER_MAX_ATTEMPTS`	`3`	Maximum claim attempts before expired running jobs stop being retried.
`OPEN_SPANNER_ALERT_WORKER_INTERVAL`	`5s`	How often the alert worker checks for queued alert evaluations.
`OPEN_SPANNER_ALERT_WORKER_LOCK_TTL`	`5m`	Lease duration for a claimed alert evaluation job.
`OPEN_SPANNER_ALERT_WORKER_TIMEOUT`	`1m`	Maximum processing time for one alert evaluation job.
`OPEN_SPANNER_ALERT_WORKER_RETRY_AFTER`	`30s`	How long to wait before a failed alert evaluation can be claimed again.
`OPEN_SPANNER_ALERT_WORKER_MAX_ATTEMPTS`	`3`	Maximum claim attempts before expired running alert jobs stop being retried.
`OPEN_SPANNER_ALERT_WORKER_BATCH_SIZE`	`100`	Maximum alert jobs claimed in one worker polling cycle.
`OPEN_SPANNER_RETENTION_PRUNE_ENABLED`	`false`	Enable automatic retention pruning.
`OPEN_SPANNER_RETENTION_PRUNE_INTERVAL`	`1h`	Background prune interval.
`OPEN_SPANNER_RETENTION_PRUNE_TIMEOUT`	`30m`	Maximum duration for one background prune run.

Docker Compose Variables

These variables are read by docker-compose.app.yml before the Open Spanner container starts:

Variable	Default	Description
`OPEN_SPANNER_HTTP_PORT`	`18081`	Host port published for the app container.
`OPEN_SPANNER_GRPC_PORT`	`18090`	Host port published for the app container's gRPC listener.
`OPEN_SPANNER_POSTGRES_PASSWORD`	`open_spanner`	Password for the bundled Postgres service and the app connection string.
`OPEN_SPANNER_EXPORT_WORKER_INTERVAL`	`5s`	Passed through to the export worker container.
`OPEN_SPANNER_EXPORT_WORKER_LOCK_TTL`	`5m`	Passed through to the export worker container.
`OPEN_SPANNER_EXPORT_WORKER_TIMEOUT`	`10m`	Passed through to the export worker container.
`OPEN_SPANNER_EXPORT_WORKER_MAX_ATTEMPTS`	`3`	Passed through to the export worker container.
`OPEN_SPANNER_ALERT_WORKER_INTERVAL`	`5s`	Passed through to the alert worker container.
`OPEN_SPANNER_ALERT_WORKER_LOCK_TTL`	`5m`	Passed through to the alert worker container.
`OPEN_SPANNER_ALERT_WORKER_TIMEOUT`	`1m`	Passed through to the alert worker container.
`OPEN_SPANNER_ALERT_WORKER_RETRY_AFTER`	`30s`	Passed through to the alert worker container.
`OPEN_SPANNER_ALERT_WORKER_MAX_ATTEMPTS`	`3`	Passed through to the alert worker container.
`OPEN_SPANNER_ALERT_WORKER_BATCH_SIZE`	`100`	Passed through to the alert worker container.
`OPEN_SPANNER_RETENTION_PRUNE_ENABLED`	`false`	Passed through to the app container.

Postgres Example

OPEN_SPANNER_DB_DRIVER=postgres
OPEN_SPANNER_POSTGRES_DSN=postgres://user:password@db.example.com:5432/open_spanner?sslmode=require
OPEN_SPANNER_DB_MAX_OPEN_CONNS=25
OPEN_SPANNER_DB_MAX_IDLE_CONNS=25

Docker Compose Variables

Postgres Example

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